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Show 94 ISLAND LIFE. [PART I. Europe at the close of the Cretaceous period was gener~1ly identical with what it is now, and perhaps even more extensive, it is absurd to suppose that it was all, or nearly all, under water during that period; or in fact that _any part of it was submerg~d, except those areas on which we actually find Cretaceous deposits, or where we have good reason to believe they have existed. The several considerations now adduced are, I think, sufficient to show that the view put forth by some naturalists (and which has met with a somewhat hasty acceptance by geologists) that our white chalk is an oceanic formation strictly comparable with that now forming at depths of a thousand fathoms and upwards in the centre of the Atlantic, giv:s a totally ~rroneous idea of the actual condition of Europe durmg that penod. Instead of being a wide ocean, with a few scattered islands, comparable to some parts of the Pacific, it formed as tru1y a Portion of the O'reat northern continent as it does now, although 0 • the inland seas of that epoch may have been more extensive and more numerous than they are at the present day.1 Fresh-water and Shore Deposits as proving the Perr~tancnce of Oontinents.-Tbe view here maintained, that all known murine deposits have been formed near the coasts of continents and islands, and that our actual continents have been in continuous existence under variously·modified forms during the whole period of known geological history, is further supported by another and I In his lecture on Geogmphical Evolution (whieh was published after the greater part of this chapter had been written) Professor Geikie expresses views in comp1ete accordance with those here advocated. He says:-" The next long era, the Cretaceous, was more remarkable for slow aecumulation of rock under the sea than for the formation of new land. During that time the Atlantic sent its waters across the whole of Europe and into Asia. But they were probably nowhere more than a few hundred feet deep over the site of our continent, even at their deepest part. Upon their bottom there gathered a vast mass of calcareous mud, composed in great part of foraminifera, corals, echinoderms, and molluscs. Our I~nglish chalk, which ranges across the north of France, BeJgium, Denmark, and the north of Germany, represents a portion of the deposits of that sea-floor." The weighty authority of the Director of the Geological Survey of Scotland may perhaps cause some geologists to modify their views as to the deepsea origin of chalk, who would have treated any arguments advanced by myaelf as not worthy of consideration. I • CHAP. VI.] GEOGRAPHICAL AND GEOLOGICAL CHANGES. 95 total~y distinct seri~s of facts.. In almost every period of geology, and mall the contments whiCh have been well examined there are found lacustrine, estuarine, or shore deposits, containi~cr the r~mains of .land animals or plants, thus demonstrating the 0 cont~ nuous existence of extensive land areas on or adjoining the sttes of our preseut continents. Beginning with the Miocene or Middle Tertiary period, we have such deposits with remain~ of land-animals, or plants, in Devonshire and Scotland in France, Switzerland, Germany, Croatia, Vienna, Greece, N~rth India, Central India, Burmah, North America, both east and west of ~he ~ocky Mountains, Greenland, and other parts of the Arctic regiOns. In the older Eocene period similar formations are widely spread in the south of England, in France, and to a~1 enormous extent on the central plateau of North America · while in the eastern states, from Maryland to Alabama ther~ are extensive marine deposits of the same age, which, fr~m the abundance of fossil remai~s of a large cetacean (Zeuglodon), must haye been formed m shallow gulfs or estuaries where these huge animals were stranded. Going back to the Creta? eous fo.rmation we have the same indications of persisting lands m the nch plant-beds of Aix-la-Chapelle, and a few other localities on the continent, as well as in coniferous fruits from the Gault of ~o!kestone; while in North America cretaceous plantbeds occur m New Jersey, Alabama, Kansas, the sources of the Missouri, the Rocky Mountains from New Mexico to the Arctic Ocean, Alaska (British Columbia), California, and in Greenland and Spitzbergen; while birds and land reptiles are found in the Cretaceous deposits of Colorado and other western distdcts. Fresh-water deposits of this age are also found on the coast of Bra.zil. In the lower part of this formation we have the fresh~water Wealden deposits of England, extending into France, Hanover, and Westphalia. In the older Oolite or Jurassic formation we have abundant proofs of continental conditions in t~e fresh-water and "dirt "-beds of the Purbecks, in the south of England, with plants, insects and mammals; the Bavarian lithographic stone, with fossil birds and insects; the earlier 4 ' forest marble" of Wiltshire, with ripple~ marks, wood and broken shells, indicative of an extensive beach; the S;ones- |